The present invention relates generally to pipe couplings, and specifically to a bolted flange assembly with a radial distribution of recessed tabs for connecting flanged sections of pipes together.
It is a common practice to mount a section of pipe to another section by means of flanges, which are attached to the ends of each section and clamped together. Bolted flanges are preferred for large pressurized lines since they establish a tight seal between the pipe sections and serve to align the sections along a common axis.
The protrusion of bolts around the circumference of the flanges presents a disadvantage in environments where space is limited. The task of providing a suitable means of connecting sections of pipe together is alleviated, to some degree by the following U.S. patents, which are incorporated herein by reference:
U.S. Pat. No. 253,482 issued to Mixer on Feb. 7, 1882; PA1 U.S. Pat. No. 2,457,077 issued to Woolsey on Dec. 21, 1948; PA1 U.S. Pat. No. 2,769,648 issued to Herman on Nov. 6, 1956; PA1 U.S. Pat. No. 3,141,686 issued to Smith et al on July 21, 1964; PA1 U.S. Pat. No. 3,466,070 issued to Spencer on Sept. 9, 1969; and
U S. Pat. No. 4,496,176 issued to Weinhold on Jan. 29, 1985.
The patents to MIXER, SMITH et al and SPENCER all illustrate pipe connections which use axially aligned bolts around the joint through flanges on the pipe. The axially aligned bolted flanges of these inventions provided an excellent means of mechanically connecting sections of pipe together. However, each individual bolt presents an external protrusion, which remains the present concern. These individual bolts may be difficult to fit into their individual slots in the flanges in situations where space is limited.
The patents of Woolsey, Herman and Weinhold all use a split clamp ring, which encompasses the mating flanges. While this is an improvement, the inventions of these references have a single locking means, such as a bolt, which forms a means of connecting the flanges together that lacks the strength of the radial distribution of axially aligned bolts. The Weinhold reference is unique in that it discloses a toggle latch which encompasses and holds together mating flanges. However, like the Woolsey, Herman and Weinhold references, the toggle latch connects flanges in a manner which may lack the strength of axially aligned bolts.
In view of the foregoing discussion, it is apparent that there currently exists the need for a means of connecting together sections of pipe which retains the advantages of the strength of axially aligned bolts, and facilitates the insertion of such bolts into the slots of flanges where space is limited. The present invention is intended to satisfy that need.